The present invention relates to tufting buttons suitable for pillows, mattresses, and upholstered furniture of the type generally contained in International Class A44b-1/18.
It is an important object of the invention to provide a tufting button collet assuring reliable locking of the twine loop conventionally used in upholstering therein.
It is a further object of the invention to provide easy looping to a collet stem consistent with the preceding object.
It is a further object of the invention to provide high strength consistent with one or both of the preceding objects.
It is a further object of the invention to provide sure gripping of a button shell on the collet consistent with one or more of the preceding objects.
It is a further object of the invention to provide a strong button hook shank without a significant increase in the overall dimensions or said shank consistent with one or more of the preceding objects.
The foregoing objects are achieved by a button construction in which the collet comprises a roughened sidewall, such as may be made by a rough mold to produce a collet sidewall with high surface roughness, of a degree known as "texture" roughness, made from a mold cut at least No. 3 roughness on the Society of Plastics Engineers 1- 6 scale and preferably No. 6 to prevent fabric sliding thereon, but not so rough as to snag or tear shell fabric. The button collet has a stem depending therefrom which is hooked around to provide a first lock between a hook end and a lower shank portion of the stem and a second series lock comprising two down-coming lips depending from the hook and shank of the stem to define a twine residence cavity of symmetrical form with downwardly facing recesses straddling a locking opening defined between the two down-coming lips. The device further defines a downwardly (toward the second lock) facing cavity between the first and second locks. The hooked stem as a whole has a low profile allowing a large thickness of the shank in the portion adjacent the symmetric cavity without increasing the overall exterior dimensions of the shank which would cause an excessive hole in fabric or vinyl material.
Other objects, features and advantages of the invention will be apparent from the following detailed description of preferred embodiments when taken in connection with the accompanying drawing.